Plural of below, or third-person singular verb meaning to cry out loudly; to shout or roar.
From Old English 'bylgan' (to swell, roar), related to the bellows that blow air. 'Below' as a shout emerged from the image of air being forced out forcefully.
The word 'bellow' (to roar) comes from the same root as 'bellows'—the tool that blows air. Both capture the idea of something expanding and releasing force explosively, whether it's a person's lungs or a blacksmith's tool.
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